Make sure you have and equip a
Sniper Rifle like
SVD (
K 35,000) or
M-700 (Free when you liberate 7 Bell Towers or buy it) to work on this achievement. I use the M-700 Sniper Rifle (Z93 in Outpost 2,3) with a
silencer to complete this.
There will have a lot of chance for you to unlock this achievement. For me, I choose to complete this when capturing a Outpost.
* Update (4th April): 2 Outposts added to the solution, all completed in "Outpost Master" (replay Outpost). Outpost 1 (Original solution): Rochan Brick Co. Storage (X: 440.4, Y 542.6)[Outpost Master]There will have 2 guards standing very close to each other and talking, they are the target (If you are playing this through Outpost master, most a bit right until you see 2 guards beside the house).
Move a bit right from your starting position and find a good spot so you can line them up, press
to steady your aim (if your sniper rifle can zoom in, I recommend you to do that for better result), aim at the head of the enemy that closet to you and kill him with a headshot, this should also kill the guard behind him.
Outpost 2: Kheta Manor (X: 450, Y: 456) [Outpost Master]You will begin on South-West side of this Outpost, move to the road (on your right) and get closer to the Outpost until you can look inside (kill the guard who is few meters away from the Outpost before he detect you.
Your target in this Outpost is the guards that standing on the right side of the camp fire (beside the house).
Move right again to find a good spot to line them up, kill the guard that closest to you (the bullet will hit the guard behind him if you do it right) to kill them in a single shot.
Outpost 3: Pranijagat School (X: 350, Y: 626) [Outpost Master]This time the Outpost is on your North-West side, move left and use the camera to find the guards, the target is beside the house. I do recommend you kill one of the guard first (left side of the screenshot) and don't let anyone find his body.
Once you done, climb to the top of the house (right side of the screenshot above) and get ready with your sniper rifle. When you sure you line them up correctly, shoot to kill them in a single shot.
Kill 2 guards in a
single shot to unlock this achievement. If you fail (or detected by enemy, all guards will move and you will miss a chance to do that), simply let yourself die / move far away from the Outpost and come back after that (First time capture) or replay the Outpost on
Menu (if you replay this through Outpost Master).